WASHINGTON (CNN) -- The former chief of the U.S. Environmental Protection Agency fought off fierce criticism Monday that the agency did not do enough to protect September 11, 2001, rescue workers from toxic pollutants.

"I fully appreciate that the events of 9/11 touched raw emotions, but I am disappointed at the misinformation, innuendo and outright falsehoods that have characterized the public discussion," Christie Todd Whitman told the U.S. House Constitution, Civil Rights and Civil Liberties Subcommittee.

Rep. Anthony D. Weiner, a Democrat from New York, at Monday's hearing read aloud from a September 13, 2001, EPA-issued press release that said air quality near the still-burning pile of rubble at Ground Zero was "unlikely to cause significant health effects."

It said "the EPA is greatly relieved to have learned that there appear to be no significant levels of asbestos dust in the air in New York City."

He cited another press release issued three days later that said asbestos levels in the air "cause us no concern."

"Those quotes were unambiguous; they were reassuring and they were dead wrong," he said. "They were literally dead wrong."

Mount Sinai Medical Center in New York last year released a study of 20,000 people concluding that 70 percent of Ground Zero workers have been affected by a type of respiratory problem.

Whitman acknowledged that dust samples taken in the financial district had contained high levels of asbestos, "but that was different from what we were finding in the air."

The distinction between asbestos in air and asbestos in dust was lost on Suzanne Mattei, former New York City executive of the Sierra Club and author of "Pollution and Deception at Ground Zero."

Now president of a consulting firm that specializes in government relations, environment and energy issues, Whitman presented a flyer she said was given to Ground Zero workers hours after the attack. It advised them of the risk of exposure to asbestos and other pollutants, cautioning them to use protective equipment, including respirators.

"It is utterly false for EPA critics to assert that I or others in the agency set about to mislead New Yorkers or the rescue workers," Whitman said.

Democratic Committee Chairman Jerrold Nadler, whose New York district includes the World Trade Center site, said the Occupational Safety and Health Administration should have, but did not, require cleanup workers to wear respirators.

In contrast, workers at the Pentagon crash site were forced to wear the protective devices and no one has become sick, he said.

But former OSHA administrator John Henshaw, who declared the financial district safe six days after 9/11, said his agency did not have jurisdiction over the firefighters and police officers who swarmed over the 16-acre site in New York.

He said OSHA had done all it could, handing out 40,000 pieces of protective equipment, including more than 7,500 negative-pressure respirators.

Whitman said the EPA would have had to invoke the Superfund Act to take control of the site and force workers to wear respirators, but doing so would have required they show "substantial and imminent danger." It did not, she said.

Even if it had been, such a move would have provoked controversy, she said.

"I'm not sure that the public would have stood for taking New York to court to take federal control of the site," she said.

Nadler also blamed state and local government officials for allowing the reoccupation of nearby buildings, including schools, that had not been properly tested or decontaminated.

"Six years later, we are just beginning to see the enormous consequences of those actions," he said. "Our government knowingly exposed thousands of U.S. citizens unnecessarily" to toxic substances.

As a result, thousands of people are at risk for asbestos-related lung cancer, he said.

Whitman acknowledged having made statements implying the air in the area -- but not directly on the pile -- was safe, but said she was simply reporting what agency scientists had told her.

"I do not regret repeating what the scientists said was appropriate," she said.

Though the National Security Council and the White House cleared the public release of information from the agency, the former governor of New Jersey said that was a move she supported.

"In my experience as a governor I always found that, at a time of crisis, you need to speak with one voice," she said.

In what witnesses said was the only time the White House made a substantive change to an EPA press release, it removed a recommendation that professionals be hired to clean buildings prior to their re-occupation, Whitman said.

"I made the determination -- rather than continue the fight, battle over that particular phrase, let the press release go out as it was," she said, adding that the recommendation appeared on subsequent press releases.

Rep. Stephen Cohen, a Tennessee Democrat, accused Whitman of failing to do her job when confronted with a White House that wanted Americans to get back to shopping and trading stocks as quickly as possible.

"Shouldn't you, as EPA administrator, be held to higher duty and implored somebody at the White House that having the market open and everybody feeling reassured was not as important as a precautionary note?" he asked.

That brought a retort from Whitman: "I couldn't disagree with you more about what you just said the White House wanted," she said.

She acknowledged she had received a call from Lawrence Lindsey, then the White House's senior economic adviser, the day after the attacks "reminding me of the importance of Wall Street -- of opening the stock market."

But she said she told him that doing so would be inappropriate "until it was safe ... That was the last I heard of that."

She added, "I felt no extreme pressure from the White House."

During her testimony Whitman also said she was not even sure that any people had been sickened by the exposure.

"I can't make that kind of a finding," she said, noting that she is not a scientist.